The present invention relates to a pneumatic tire having an excellent water-repellency.
A number of techniques of a tread pattern formed on the tread surface (i.e., ground-contacting surface) of the tire have been proposed in the prior art, in terms of the water-repellency, the steering stability and so on. However, none of them have satisfied water-repellency yet.
Generally speaking, it is natural to lay stress on the repellency of the tire if the running on a poorly drained road such as a superhighway is taken into consideration. Water-repelling grooves have to be provided on the tread surface by noting the grounding pattern taken when a vehicle runs on such road.
The posture of the tire relative to the road surface is determined according to the so-called "wheel alignment" such as the toe-in or the camber angle. Although these are fundamental, it is necessary for considering the water-repellency of the tire to note that the grounding pattern has its shape varied according to the wheel alignment when the tire is attached to the vehicle.
The arrangement of the water-repelling grooves made heretofore has been designed without paying attention to the above-specified wheel alignment so that the sufficient repellency cannot be achieved.